Information about a deadly Legionnaires' cluster in Sydney's inner-west was given to the NSW health minister a "few days" before the public was notified, following the death of a patient from the disease.
The elderly male patient died in Concord Hospital mid-last week, NSW Health revealed on Tuesday.
His death was part of a small cluster of four cases in the inner-west suburb of Burwood being investigated by Sydney Local Health District's Public Health Unit.
The cases have prompted inspections of at least nine cooling towers in local buildings, including the Westfield Burwood shopping centre and Burwood Shopping Plaza.
The disease, which causes fever, chills, a cough and shortness of breath, is known to mostly affect middle-aged and older people, particularly smokers and people with chronic lung disease or another underlying health problem.
Health Minister Jillian Skinner has brushed off questions about sitting on the information before making the public aware of the disease cluster at Burwood, while admitting she knew about it "a few days ago" and was told about the man's death on Tuesday.
Skinner told reporters on Wednesday the information was released "when we actually found out the actual cause and location of the cluster".
She has moved to play down the risk "to the majority of people", saying there have been about 100 Legionnaires' cases every year for the last two decades - about two-thirds from cooling towers - with 2016 largely consistent with previous years.
Sydney does not have an outbreak "in plague proportions", Skinner said.
"People should not panic," she said.
"This is not something that is going to attack everyone.
"I am advised that people can walk through a shopping centre or a street where there's contaminated droplets in the air and not be affected."
Jeremy McAnulty, director of Health Protection NSW, said the number of Legionnaires cases was "on track" with expectations.
"Although we've had a large number of relatively small clusters, they haven't been big clusters," he told reporters.
McAnulty said authorities were working to ensure cooling towers were being maintained properly.
Last week, Vicky Sheppeard, director of the communicable diseases branch at NSW Health, said five of the 89 cooling towers and areas tested in the CBD for the potentially deadly bacteria had returned positive results during preliminary testing.Do you have an idea for a story?
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